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Philosophy

The Principle of Double Effect and Its Application to Collateral Damage

Quick fact

The Principle of Double Effect was formalized by Thomas Aquinas in the 13th century to justify killing in self-defense, and it remains a cornerstone of modern just war theory and international law.

Why this is interesting

You order a missile strike on a weapons depot, knowing civilians will die. Are you morally responsible for their deaths? The Principle of Double Effect says maybe not — but it all depends on what you intend.